Recently, liquid crystal displays (LCD) have been widely applied in electrical products, due to the rapid progress of optical technology and semiconductor technology. Moreover, with the advantages of high image quality, compact size, light weight, low driving voltage, and low power consumption, LCDs have been introduced into portable computers, personal digital assistants, color televisions, and are gradually replacing the cathode ray tubes (CRT) used in conventional displays. LCDs are becoming the mainstream display apparatus.
Notebook computers are convenient to carry and therefore are often carried to business meetings. In different environments, the notebook computer has to provide different display angles to enhance the demonstration capabilities thereof. However, due to a conventional restricted display angle, the notebook computer cannot provide all viewers with clear images on the display. Moreover, due to software and hardware improvements, a tablet personal computer (Tablet PC) introduces a computer with a hand writing input device on the display thereof. The tablet PC changes the input habits of the computer user and advances the information industry to a new milestone.  A notebook/tablet dual-purpose computer with high processing performance combines the hand writing input device on the display panel and the keyboard input of the notebook computer. The notebook/tablet dual-purpose computer provides a humanizing input interface for a user who usually works in a moving environment. The display of a notebook/tablet dual-purpose computer can rotate about 180 degrees so that viewers around the tablet PC can see the information and images on the display more easily than before.
In general, the notebook/tablet dual-purpose computer with a rotatable liquid crystal display provides not only various display functions but also an optical disk playing function. However, the control button for the optical disk is covered by the liquid crystal display when the liquid crystal display locks onto the computer base and the liquid crystal display panel is exposed. Therefore, if the user wishes to play an optical disk, the liquid crystal display has to be first released from the computer base. Otherwise, the notebook/tablet dual-purpose computer has to turn on a central processing unit thereof to run an operating system and an application software for operating the optical disk.
Therefore, there is a need for quick and effective operation of the optical disk drive for a notebook/tablet dual-purpose computer with a rotatable liquid crystal display.